(1) Field of the Invention
The present invention relates to a process for regenerating an ink sheet, in particular relates to a process for regenerating an ink sheet comprising a base layer and an ink layer formed on one side of said base layer, wherein the ink layer of the ink sheet (used ink sheet) after part of the ink layer has been transferred onto an object-to-be-recorded for the purpose of recording is restored to the former condition.
(2) Description of the Prior Art
Up to the present, there are known (a) an electro-transfer recording method which comprises the steps of superimposing, on a recording medium (object-to-be-recorded), an ink layer of an ink sheet comprising an electrically conductive base layer and an ink layer superimposed on said base layer; bringing the base layer of the ink sheet into contact with a needle-like recording electrode and a return electrode disposed at a fixed interval from said recording electrode; impressing an image signal voltage between the recording electrode and the return electrode for applying an electric current to the ink sheet; and melting part of the ink layer by means of Joule heat caused by the application of an electric current to thereby transfer the resulting melt onto the object-to-be-recorded, and (b) a heat-transfer recording method which comprises the steps of superimposing an object-to-be-recorded on an ink layer of an ink sheet comprising an base layer and an ink layer superimposed on said base layer; disposing a heating element on the base layer side; applying an image signal electric current to this heating element for heating the heating element; thus heating the base layer and the ink layer to thereby melt part of the ink layer; and transferring the resulting melt onto the object-to-be-recorded.
And, a process for regenerating an ink sheet is also known which comprises adhering or charging a fresh ink into the hollowed parts formed in the ink layer after part of the ink layer has been heat-transferred onto the object-to-be-recorded by means of said electro-transfer recording method and said heat-transfer recording method. As the regenerating processes of this type there can be enumerated for instance (i) a process comprising the steps of impressing a fixed electric charge onto the surface of an ink layer of an ink sheet by means of a corona charger; thereafter supplying the ink layer with a powder ink having a polarity opposite to that of said electric charge; and adhering the powder ink to the ink layer by the action of electrostatic force, (ii) a process comprising the steps of melting a thermo-fusible ink and coating an ink layer with this melt; and the like.
However, the process (i) is defective in that since the charge amount at the hollowed part of the ink layer is smaller than that at the portion other than the hollowed part of the ink layer in such a state that said electric charge has been impressed onto the surface of the ink layer by means of the corona charger, it is impossible to supply a sufficient amount of powder ink to the hollowed part of the ink layer, and therefore the hollowed part still remains on the surface of the ink layer even after regeneration.
The process (ii) is also defective in that since said process is not designed to supply a larger amount of ink to the hollowed part in comparison with the portion other than the hollowed part, the hollowed part still remains on the surface of the ink layer even after regeneration.